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Mars colonists could create a carbon dioxide plasma in order to supply oxygen to their settlement(s):
The atmosphere on Mars is 96 per cent carbon dioxide, says Vasco Guerra at the University of Lisbon in Portugal. This can be split to extract breathable oxygen and carbon monoxide, a fuel that could give us a "gas station on the Red Planet", he says. He and his team calculate that creating a carbon dioxide plasma — a mush of ions made by passing an electric current through a gas — could split carbon dioxide from oxygen more easily on Mars than on Earth.
The lower atmospheric pressure on Mars would allow us to create plasmas without the vacuum pumps or compressors necessary on Earth. Also, the temperature of around -60°C is just right to let the plasma more easily break one of the chemical bonds that keeps carbon and oxygen tightly bound, while preventing the carbon dioxide from re-forming.
For now, this is largely theoretical, but they say such a system needing only 150 to 200 Watts for 4 hours each 25-hour Mars day could produce 8 to 16 kilograms of oxygen. "The International Space Station currently consumes oxygen in the range of 2 to 5 kilograms per day, so this would be enough to support a small settlement," says Guerra.
The case for in situ resource utilisation for oxygen production on Mars by nonequilibrium plasmas (open, DOI: 10.1088/1361-6595) (DX)
(Score: 3, Informative) by Anonymous Coward on Friday October 27 2017, @04:58PM (2 children)
I only got as far as two errors and don't care to look further.
1. Splitting CO2 will give you 1mol CO and .5mol O2. So you need 4X more oxygen than you get from this process.
2. Your numbers are for CO2 at 1 atmosphere, not Martian pressures. standard enthalpy change of combustion [wikipedia.org]
Aside from those, we are learning a lot about the intersection of quantum mechanics and materials science. That said, your 2.88 MJ -> 141.5 JM is a pretty big gap to cross, even running the same process to get the missing oxygen would only shift the cost to 12ish MJ. Kinetic energy is pretty linearly dependent on temperature, so Mars temps drastically lower the total energy in the system.
(Score: 3, Funny) by frojack on Friday October 27 2017, @08:57PM
No wonder nobody likes to go to the movies with you.
And you thought it was because you ate all the popcorn!
No, you are mistaken. I've always had this sig.
(Score: 3, Interesting) by c0lo on Friday October 27 2017, @10:24PM
Thanks.
Point 1 doesn't show an error. you have 4kg of O2 = 250mol you need 500 mol of CO2 to get that oxygen and you'll obtain 500 mol of CO as result.
Point 2 is valid. The difference 2.88->141.5MJ is the energy required to compress the gases to 1atm and heat them for -60C to 0C.
At least for oxygen, one will need to do both if that oxygen is meant for breathing.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford